who made you the boss of what is a word.
According to Eric P. Hamp in the journal "American Speech" the etymology of the word SUPERCALIFRAGELISTICEXPIALIDOCIOUS is the concatenation of supercalifragilistic and expialidocious, you can go search a library and find the journal and look it up.

on the other hand my example works just as good with SUPERCALIFRAGELISTICEXPIALIDOCIOUS

on the other hand it is easy to see that SUPERCALIFRAGELISTICEXPIALIDOCIOUS is a compound because normally icex does not make the sound ic+ex